In most conventional refrigerators as shown in FIG. 5, the cool air which is introduced into a refrigerating room 11 is circulated within a vegetable room 12 by means of a blowing fan 10 so that a vegetable box 20 is indirectly cooled. Such a method of cooling is not very effective, and, in an attempt to give a solution to this problem, there was proposed another vegetable box cooling apparatus. This apparatus is proposed in Korean Utility Model Laid-Open No. 90-7062, and is constituted as described below. That is, a projected front portion with a plurality of cool air passing holes formed thereon is provided on a frontal plate of the vegetable box, and an upper flange portion is formed vertically relative to the projected front portion and integrally with it. Further, a plurality of engaging protuberances are projected in the horizontal direction from the outer surface of the upper flange portion, while a gasket of a proper shape is installed on the upper flange portion, thereby making the cool air within the refrigerating room smoothly circulate around the vegetable box.
Meanwhile, Japanese Utility Model Laid-Open No. 55-8805 discloses another vegetable box cooling apparatus. In this apparatus, a part of the cool air which is supplied into the refrigerating room is introduced through a cooling duct installed on the wall of the vegetable room into the vegetable room. Further, still another apparatus is disclosed in Japanese Utility Model Laid Open No. 1-91871. In this apparatus, a temperature sensor is installed on the vegetable box, and a damper which is selectively opened or closed by control signal transmitted from a controller (not shown) is installed on a vegetable box passage which is formed around the vegetable box, so that the damper should be able to selectively supply or cut off the cool air to and from the vegetable room or the vegetable room passage.
In the above described conventional apparatuses, the vegetable room and the vegetable box are almost sealingly divided , and the vegetables within the vegetable box are indirectly cooled through the surrounding walls of the vegetable box, with the result that there occurs temperature difference between the vegetable room and the vegetable box. Particularly, in the initial operating stage of the refrigerator, the cooling speed of the vegetable box is very slow, and therefore, speedy cooling of vegetables becomes difficult. Further, during the operation after the initial operating stage of the refrigerator, the internal temperature of the vegetable box is maintained higher than that of the vegetable room, with the result that the stored vegetables are severely dried or degenerated, thereby making it impossible to store vegetables in a fresh state for a long time.